/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "apr_network_io.h" #include "apr_strings.h" #define APR_WANT_STRFUNC #include "apr_want.h" #include "ap_config.h" #include "httpd.h" #include "http_config.h" #include "http_core.h" #include "ap_listen.h" #include "http_log.h" #include "mpm.h" #include "mpm_common.h" AP_DECLARE_DATA ap_listen_rec *ap_listeners = NULL; static ap_listen_rec *old_listeners; static int ap_listenbacklog; static int send_buffer_size; static int receive_buffer_size; /* TODO: make_sock is just begging and screaming for APR abstraction */ static apr_status_t make_sock(apr_pool_t *p, ap_listen_rec *server) { apr_socket_t *s = server->sd; int one = 1; #if APR_HAVE_IPV6 #ifdef AP_ENABLE_V4_MAPPED int v6only_setting = 0; #else int v6only_setting = 1; #endif #endif apr_status_t stat; #ifndef WIN32 stat = apr_socket_opt_set(s, APR_SO_REUSEADDR, one); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_CRIT, stat, p, "make_sock: for address %pI, apr_socket_opt_set: (SO_REUSEADDR)", server->bind_addr); apr_socket_close(s); return stat; } #endif stat = apr_socket_opt_set(s, APR_SO_KEEPALIVE, one); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_CRIT, stat, p, "make_sock: for address %pI, apr_socket_opt_set: (SO_KEEPALIVE)", server->bind_addr); apr_socket_close(s); return stat; } #if APR_HAVE_IPV6 if (server->bind_addr->family == APR_INET6) { stat = apr_socket_opt_set(s, APR_IPV6_V6ONLY, v6only_setting); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_CRIT, stat, p, "make_sock: for address %pI, apr_socket_opt_set: " "(IPV6_V6ONLY)", server->bind_addr); apr_socket_close(s); return stat; } } #endif /* * To send data over high bandwidth-delay connections at full * speed we must force the TCP window to open wide enough to keep the * pipe full. The default window size on many systems * is only 4kB. Cross-country WAN connections of 100ms * at 1Mb/s are not impossible for well connected sites. * If we assume 100ms cross-country latency, * a 4kB buffer limits throughput to 40kB/s. * * To avoid this problem I've added the SendBufferSize directive * to allow the web master to configure send buffer size. * * The trade-off of larger buffers is that more kernel memory * is consumed. YMMV, know your customers and your network! * * -John Heidemann 25-Oct-96 * * If no size is specified, use the kernel default. */ if (send_buffer_size) { stat = apr_socket_opt_set(s, APR_SO_SNDBUF, send_buffer_size); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_WARNING, stat, p, "make_sock: failed to set SendBufferSize for " "address %pI, using default", server->bind_addr); /* not a fatal error */ } } if (receive_buffer_size) { stat = apr_socket_opt_set(s, APR_SO_RCVBUF, receive_buffer_size); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_WARNING, stat, p, "make_sock: failed to set ReceiveBufferSize for " "address %pI, using default", server->bind_addr); /* not a fatal error */ } } #if APR_TCP_NODELAY_INHERITED ap_sock_disable_nagle(s); #endif if ((stat = apr_socket_bind(s, server->bind_addr)) != APR_SUCCESS) { ap_log_perror(APLOG_MARK, APLOG_STARTUP|APLOG_CRIT, stat, p, "make_sock: could not bind to address %pI", server->bind_addr); apr_socket_close(s); return stat; } if ((stat = apr_socket_listen(s, ap_listenbacklog)) != APR_SUCCESS) { ap_log_perror(APLOG_MARK, APLOG_STARTUP|APLOG_ERR, stat, p, "make_sock: unable to listen for connections " "on address %pI", server->bind_addr); apr_socket_close(s); return stat; } #ifdef WIN32 /* I seriously doubt that this would work on Unix; I have doubts that * it entirely solves the problem on Win32. However, since setting * reuseaddr on the listener -prior- to binding the socket has allowed * us to attach to the same port as an already running instance of * Apache, or even another web server, we cannot identify that this * port was exclusively granted to this instance of Apache. * * So set reuseaddr, but do not attempt to do so until we have the * parent listeners successfully bound. */ stat = apr_socket_opt_set(s, APR_SO_REUSEADDR, one); if (stat != APR_SUCCESS && stat != APR_ENOTIMPL) { ap_log_perror(APLOG_MARK, APLOG_CRIT, stat, p, "make_sock: for address %pI, apr_socket_opt_set: (SO_REUSEADDR)", server->bind_addr); apr_socket_close(s); return stat; } #endif server->sd = s; server->active = 1; #ifdef MPM_ACCEPT_FUNC server->accept_func = MPM_ACCEPT_FUNC; #else server->accept_func = NULL; #endif return APR_SUCCESS; } static const char* find_accf_name(server_rec *s, const char *proto) { const char* accf; core_server_config *conf = ap_get_module_config(s->module_config, &core_module); if (!proto) { return NULL; } accf = apr_table_get(conf->accf_map, proto); if (accf && !strcmp("none", accf)) { return NULL; } return accf; } static void ap_apply_accept_filter(apr_pool_t *p, ap_listen_rec *lis, server_rec *server) { apr_socket_t *s = lis->sd; const char *accf; apr_status_t rv; const char *proto; proto = lis->protocol; if (!proto) { proto = ap_get_server_protocol(server); } accf = find_accf_name(server, proto); if (accf) { #if APR_HAS_SO_ACCEPTFILTER rv = apr_socket_accept_filter(s, apr_pstrdup(p, accf), apr_pstrdup(p,"")); if (rv != APR_SUCCESS && !APR_STATUS_IS_ENOTIMPL(rv)) { ap_log_perror(APLOG_MARK, APLOG_WARNING, rv, p, "Failed to enable the '%s' Accept Filter", accf); } #else rv = apr_socket_opt_set(s, APR_TCP_DEFER_ACCEPT, 30); if (rv != APR_SUCCESS && !APR_STATUS_IS_ENOTIMPL(rv)) { ap_log_perror(APLOG_MARK, APLOG_WARNING, rv, p, "Failed to enable APR_TCP_DEFER_ACCEPT"); } #endif } } static apr_status_t close_listeners_on_exec(void *v) { ap_close_listeners(); return APR_SUCCESS; } static const char *alloc_listener(process_rec *process, char *addr, apr_port_t port, const char* proto) { ap_listen_rec **walk, *last; apr_status_t status; apr_sockaddr_t *sa; int found_listener = 0; /* see if we've got an old listener for this address:port */ for (walk = &old_listeners; *walk;) { sa = (*walk)->bind_addr; /* Some listeners are not real so they will not have a bind_addr. */ if (sa) { ap_listen_rec *new; apr_port_t oldport; oldport = sa->port; /* If both ports are equivalent, then if their names are equivalent, * then we will re-use the existing record. */ if (port == oldport && ((!addr && !sa->hostname) || ((addr && sa->hostname) && !strcmp(sa->hostname, addr)))) { new = *walk; *walk = new->next; new->next = ap_listeners; ap_listeners = new; found_listener = 1; continue; } } walk = &(*walk)->next; } if (found_listener) { return NULL; } if ((status = apr_sockaddr_info_get(&sa, addr, APR_UNSPEC, port, 0, process->pool)) != APR_SUCCESS) { ap_log_perror(APLOG_MARK, APLOG_CRIT, status, process->pool, "alloc_listener: failed to set up sockaddr for %s", addr); return "Listen setup failed"; } /* Initialize to our last configured ap_listener. */ last = ap_listeners; while (last && last->next) { last = last->next; } while (sa) { ap_listen_rec *new; /* this has to survive restarts */ new = apr_palloc(process->pool, sizeof(ap_listen_rec)); new->active = 0; new->next = 0; new->bind_addr = sa; new->protocol = apr_pstrdup(process->pool, proto); /* Go to the next sockaddr. */ sa = sa->next; status = apr_socket_create(&new->sd, new->bind_addr->family, SOCK_STREAM, 0, process->pool); #if APR_HAVE_IPV6 /* What could happen is that we got an IPv6 address, but this system * doesn't actually support IPv6. Try the next address. */ if (status != APR_SUCCESS && !addr && new->bind_addr->family == APR_INET6) { continue; } #endif if (status != APR_SUCCESS) { ap_log_perror(APLOG_MARK, APLOG_CRIT, status, process->pool, "alloc_listener: failed to get a socket for %s", addr); return "Listen setup failed"; } /* We need to preserve the order returned by getaddrinfo() */ if (last == NULL) { ap_listeners = last = new; } else { last->next = new; last = new; } } return NULL; } /* Evaluates to true if the (apr_sockaddr_t *) addr argument is the * IPv4 match-any-address, 0.0.0.0. */ #define IS_INADDR_ANY(addr) ((addr)->family == APR_INET \ && (addr)->sa.sin.sin_addr.s_addr == INADDR_ANY) /* Evaluates to true if the (apr_sockaddr_t *) addr argument is the * IPv6 match-any-address, [::]. */ #define IS_IN6ADDR_ANY(addr) ((addr)->family == APR_INET6 \ && IN6_IS_ADDR_UNSPECIFIED(&(addr)->sa.sin6.sin6_addr)) /** * Create, open, listen, and bind all sockets. * @param process The process record for the currently running server * @return The number of open sockets */ static int open_listeners(apr_pool_t *pool) { ap_listen_rec *lr; ap_listen_rec *next; ap_listen_rec *previous; int num_open; const char *userdata_key = "ap_open_listeners"; void *data; #if AP_NONBLOCK_WHEN_MULTI_LISTEN int use_nonblock; #endif /* Don't allocate a default listener. If we need to listen to a * port, then the user needs to have a Listen directive in their * config file. */ num_open = 0; previous = NULL; for (lr = ap_listeners; lr; previous = lr, lr = lr->next) { if (lr->active) { ++num_open; } else { #if APR_HAVE_IPV6 ap_listen_rec *cur; int v6only_setting; int skip = 0; /* If we have the unspecified IPv4 address (0.0.0.0) and * the unspecified IPv6 address (::) is next, we need to * swap the order of these in the list. We always try to * bind to IPv6 first, then IPv4, since an IPv6 socket * might be able to receive IPv4 packets if V6ONLY is not * enabled, but never the other way around. * Note: In some configurations, the unspecified IPv6 address * could be even later in the list. This logic only corrects * the situation where it is next in the list, such as when * apr_sockaddr_info_get() returns an IPv4 and an IPv6 address, * in that order. */ if (lr->next != NULL && IS_INADDR_ANY(lr->bind_addr) && lr->bind_addr->port == lr->next->bind_addr->port && IS_IN6ADDR_ANY(lr->next->bind_addr)) { /* Exchange lr and lr->next */ next = lr->next; lr->next = next->next; next->next = lr; if (previous) { previous->next = next; } else { ap_listeners = next; } lr = next; } /* If we are trying to bind to 0.0.0.0 and a previous listener * was :: on the same port and in turn that socket does not have * the IPV6_V6ONLY flag set; we must skip the current attempt to * listen (which would generate an error). IPv4 will be handled * on the established IPv6 socket. */ if (IS_INADDR_ANY(lr->bind_addr)) { for (cur = ap_listeners; cur != lr; cur = cur->next) { if (lr->bind_addr->port == cur->bind_addr->port && IS_IN6ADDR_ANY(cur->bind_addr) && apr_socket_opt_get(cur->sd, APR_IPV6_V6ONLY, &v6only_setting) == APR_SUCCESS && v6only_setting == 0) { /* Remove the current listener from the list */ previous->next = lr->next; lr = previous; /* maintain current value of previous after * post-loop expression is evaluated */ skip = 1; break; } } if (skip) { continue; } } #endif if (make_sock(pool, lr) == APR_SUCCESS) { ++num_open; lr->active = 1; } else { #if APR_HAVE_IPV6 /* If we tried to bind to ::, and the next listener is * on 0.0.0.0 with the same port, don't give a fatal * error. The user will still get a warning from make_sock * though. */ if (lr->next != NULL && IS_IN6ADDR_ANY(lr->bind_addr) && lr->bind_addr->port == lr->next->bind_addr->port && IS_INADDR_ANY(lr->next->bind_addr)) { /* Remove the current listener from the list */ if (previous) { previous->next = lr->next; } else { ap_listeners = lr->next; } /* Although we've removed ourselves from the list, * we need to make sure that the next iteration won't * consider "previous" a working IPv6 '::' socket. * Changing the family is enough to make sure the * conditions before make_sock() fail. */ lr->bind_addr->family = AF_INET; continue; } #endif /* fatal error */ return -1; } } } /* close the old listeners */ for (lr = old_listeners; lr; lr = next) { apr_socket_close(lr->sd); lr->active = 0; next = lr->next; } old_listeners = NULL; #if AP_NONBLOCK_WHEN_MULTI_LISTEN /* if multiple listening sockets, make them non-blocking so that * if select()/poll() reports readability for a reset connection that * is already forgotten about by the time we call accept, we won't * be hung until another connection arrives on that port */ use_nonblock = (ap_listeners && ap_listeners->next); for (lr = ap_listeners; lr; lr = lr->next) { apr_status_t status; status = apr_socket_opt_set(lr->sd, APR_SO_NONBLOCK, use_nonblock); if (status != APR_SUCCESS) { ap_log_perror(APLOG_MARK, APLOG_STARTUP|APLOG_ERR, status, pool, "unable to control socket non-blocking status"); return -1; } } #endif /* AP_NONBLOCK_WHEN_MULTI_LISTEN */ /* we come through here on both passes of the open logs phase * only register the cleanup once... otherwise we try to close * listening sockets twice when cleaning up prior to exec */ apr_pool_userdata_get(&data, userdata_key, pool); if (!data) { apr_pool_userdata_set((const void *)1, userdata_key, apr_pool_cleanup_null, pool); apr_pool_cleanup_register(pool, NULL, apr_pool_cleanup_null, close_listeners_on_exec); } return num_open ? 0 : -1; } AP_DECLARE(int) ap_setup_listeners(server_rec *s) { server_rec *ls; server_addr_rec *addr; ap_listen_rec *lr; int num_listeners = 0; const char* proto; int found; for (ls = s; ls; ls = ls->next) { proto = ap_get_server_protocol(ls); if (!proto) { found = 0; /* No protocol was set for this vhost, * use the default for this listener. */ for (addr = ls->addrs; addr && !found; addr = addr->next) { for (lr = ap_listeners; lr; lr = lr->next) { if (apr_sockaddr_equal(lr->bind_addr, addr->host_addr) && lr->bind_addr->port == addr->host_port) { ap_set_server_protocol(ls, lr->protocol); found = 1; break; } } } if (!found) { /* TODO: set protocol defaults per-Port, eg 25=smtp */ ap_set_server_protocol(ls, "http"); } } } if (open_listeners(s->process->pool)) { return 0; } for (lr = ap_listeners; lr; lr = lr->next) { num_listeners++; found = 0; for (ls = s; ls && !found; ls = ls->next) { for (addr = ls->addrs; addr && !found; addr = addr->next) { if (apr_sockaddr_equal(lr->bind_addr, addr->host_addr) && lr->bind_addr->port == addr->host_port) { found = 1; ap_apply_accept_filter(s->process->pool, lr, ls); } } } if (!found) { ap_apply_accept_filter(s->process->pool, lr, s); } } return num_listeners; } AP_DECLARE_NONSTD(void) ap_close_listeners(void) { ap_listen_rec *lr; for (lr = ap_listeners; lr; lr = lr->next) { apr_socket_close(lr->sd); lr->active = 0; } } AP_DECLARE(void) ap_listen_pre_config(void) { old_listeners = ap_listeners; ap_listeners = NULL; ap_listenbacklog = DEFAULT_LISTENBACKLOG; } AP_DECLARE_NONSTD(const char *) ap_set_listener(cmd_parms *cmd, void *dummy, int argc, char *const argv[]) { char *host, *scope_id, *proto; apr_port_t port; apr_status_t rv; const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } if (argc < 1 || argc > 2) { return "Listen requires 1 or 2 arguments."; } rv = apr_parse_addr_port(&host, &scope_id, &port, argv[0], cmd->pool); if (rv != APR_SUCCESS) { return "Invalid address or port"; } if (host && !strcmp(host, "*")) { host = NULL; } if (scope_id) { /* XXX scope id support is useful with link-local IPv6 addresses */ return "Scope id is not supported"; } if (!port) { return "Port must be specified"; } if (argc != 2) { if (port == 443) { proto = "https"; } else { proto = "http"; } } else { proto = apr_pstrdup(cmd->pool, argv[1]); ap_str_tolower(proto); } return alloc_listener(cmd->server->process, host, port, proto); } AP_DECLARE_NONSTD(const char *) ap_set_listenbacklog(cmd_parms *cmd, void *dummy, const char *arg) { int b; const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } b = atoi(arg); if (b < 1) { return "ListenBacklog must be > 0"; } ap_listenbacklog = b; return NULL; } AP_DECLARE_NONSTD(const char *) ap_set_send_buffer_size(cmd_parms *cmd, void *dummy, const char *arg) { int s = atoi(arg); const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } if (s < 512 && s != 0) { return "SendBufferSize must be >= 512 bytes, or 0 for system default."; } send_buffer_size = s; return NULL; } AP_DECLARE_NONSTD(const char *) ap_set_receive_buffer_size(cmd_parms *cmd, void *dummy, const char *arg) { int s = atoi(arg); const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } if (s < 512 && s != 0) { return "ReceiveBufferSize must be >= 512 bytes, or 0 for system default."; } receive_buffer_size = s; return NULL; }